Machining method and end effector

Abstract

Processing is performed along the surface of the workpiece, according to the position and shape of the workpiece. [Solution] A machining robot (11) extends a search tool (15) toward a machining surface search position (83), which is three points near a machining position (81) of a workpiece (3), acquires the search coordinates where the search tool (15) comes into contact with the machining surface search position (83), calculates a tangent plane (84) of the surface of the workpiece (3) at the machining position (81) relative to the machining robot (11) based on the acquired three search coordinates, and machines the machining position (81) with the machining tool (17) so that the spindle (13c) to which the machining tool (17) is attached is perpendicular to the tangent plane (84).

Description

[Technical Field]

[0001] The present invention relates to a machining method and an end effector. [Background technology]

[0002] The thread machining device disclosed in JP 2009-248279 A includes a robot, a lifting mechanism, a rotation mechanism, a support, a tap, a sensor, a computing device, and a control box. A robot arm is disposed at the tip of the robot. The lifting mechanism is supported on the tip of the robot arm via a flange. The rotation mechanism is supported by the lifting mechanism. The support is disposed at the tip of the rotation mechanism. The tap is supported by the support. A sensor is disposed on the top surface of the robot and detects the inclination of the robot arm. The computing device calculates information obtained from the sensor. The control box operates the lifting mechanism and the rotation mechanism based on information obtained from the computing device. Summary of the Invention [Problem to be solved by the invention]

[0003] It can be difficult to accurately place the workpiece on the robot, and the shape of the workpiece may differ from the drawing. In these cases, it is difficult to machine the workpiece by tracing its surface. The present invention aims to perform machining along the surface of a workpiece in accordance with the position and shape of the workpiece. [Means for solving the problem]

[0004] A first aspect of the present invention is The machining robot extends a search tool toward three points near the machining position of the workpiece, which are machining surface search positions, and acquires search coordinates where the search tool comes into contact with the machining surface search positions; Calculating a tangent plane to the surface of the workpiece at the processing position relative to the processing robot based on the acquired three search coordinates; The machining robot processes the machining position with the machining tool so that a spindle to which the machining tool is attached is perpendicular to the tangential plane. It is a processing method.

[0005] A second aspect of the present invention is An end effector attached to a processing robot, Body and a ram installed on the body so as to be able to advance and retreat; a main shaft to which a rotary tool can be attached and which is rotatably supported by the ram; a search cylinder disposed in the body, A cylinder body and a probe extending parallel to the main shaft, arranged in the cylinder body so as to be extendable and retractable, and capable of measuring the amount of extension when a tip portion thereof comes into contact with a workpiece; a search cylinder having The end effector has:

[0006] The machining includes drilling, tapping, end milling, and face milling. When performing end milling or face milling, the cutting end effector may have an X-axis feed shaft that feeds the spindle in a direction perpendicular to the spindle. In this case, the body may be disposed on the X-axis feed shaft. The end effector feeds the spindle in a direction perpendicular to the spindle. The processing robot may include an end effector exchange device. The processing robot may be equipped with an exchangeable end effector for cutting, a 3D scanner, or a searching end effector. The cutting effector may have a body, a ram, and a spindle. The body is supported by an arm. The ram moves the spindle forward and backward relative to the body. The shape of the processing drawing may be stretched or the curvature may be changed to fit the three-dimensional model obtained by measurement, and the processing position may be calculated. [Effects of the Invention]

[0007] According to the present invention, machining can be performed along the surface of the workpiece in accordance with the position and shape of the workpiece. [Brief explanation of the drawings]

[0008] [Figure 1] Processing device of embodiment 1 [Figure 2] Arrow II view of Figure 1 [Figure 3] Processing status of workpiece by the processing device of embodiment 1 [Figure 4] Processing device of embodiment 2 [Figure 5] Processing device of embodiment 3 [Figure 6] Processing device of embodiment 4 DETAILED DESCRIPTION OF THE INVENTION

[0009] <Embodiment 1> 1, the processing device 10 of this embodiment has a robot (processing robot) 11, an end effector 13, and a holding jig 4. Below, a case where the processing device 10 performs drilling will be described.

[0010] The robot 11 is a vertical articulated robot. The robot 11 has an arm 11a, a control device 11b, and a reference position 11c. The robot 11 is fixed to a floor surface 1. The reference position 11c is the intersection of the central axis of a first axis (not shown) of the robot 11 and the floor surface 1.

[0011] The end effector 13 has a body 13a, a ram 13b, a main shaft 13c, and a linear feed shaft 13f. The body 13a is disposed at the tip of the arm 11a. The ram 13b is disposed on the body 13a so as to be able to advance and retreat. The ram 13b extends along the main shaft 13c. The main shaft 13c is supported by the ram 13b so as to be rotatable about a central axis 13d. A tool can be attached to the main shaft 13c. For example, the main shaft 13c has a draw bar (not shown) and a main shaft hole (not shown). The linear feed shaft 13f is disposed on the body 13a. The linear feed shaft 13f guides the ram 13b along the central axis 13d and moves the ram 13b. The holding jig 4 is fixed to the floor surface 1. The holding jig 4 holds the workpiece 3.

[0012] The processing method of this embodiment will be described. As shown in FIG. 1, the workpiece 3 has a surface 3a that is a curved surface. As shown in FIG. 2, a machining position 81 is located on the surface 3a. The machining position 81 is indicated by a machining drawing. Three search positions (machining surface search positions) 83 are determined around the machining position 81. The search positions 83 are determined on the surface 3a, for example, so as to surround the machining position 81. Preferably, the search positions 83 are determined so that they become vertices of an equilateral triangle when projected onto a plane facing the surface. The search positions 83 are located near the machining positions 81. The search positions 83 are determined so that there are no large steps or chips on the surface 3a inside an area 82 that connects the search positions 83 in a straight line.

[0013] As shown in Fig. 1, a touch probe (search tool) 15 is attached to the spindle 13c. The robot 11 adjusts the arm 11a to bring the touch probe 15 into contact with a search position 83 on the workpiece 3. Preferably, the robot 11 brings a contactor (not shown) of the touch probe 15 into contact with the surface 3a so that it is approximately perpendicular to the surface 3a. The control device 11b acquires the coordinates of the three search positions 83 relative to the reference position 11c. The control device 11b calculates a tangent plane 84 that passes through the three search positions 83 relative to the reference position 11c.

[0014] Next, as shown in Fig. 3, the drill 17 is attached to the spindle 13c. The control device 11b positions the end effector 13 so that the central axis 13d is perpendicular to the tangent plane 84 and the machining position 81 passes through the central axis 13d. At this time, a gap is provided between the drill 17 and the surface 3a.

[0015] Next, the processing device 10 rotates the spindle 13c and sends the ram 13b toward the workpiece 3. The drill 17 cuts into the workpiece 3 to drill a hole. When the drill 17 reaches a predetermined depth, the processing device 10 retracts the ram 13b and removes the drill 17 from the workpiece 3. When the workpiece 3 has a plurality of machining positions 81, the above machining procedure may be repeated for each machining position 81.

[0016] When the workpiece 3 has a plurality of machining positions 81, the tangent planes 84 for each machining position 81 may be determined collectively with the touch probe 15 attached to the spindle 13c. After that, the touch probe 15 attached to the spindle 13c may be replaced with a drill 17, and holes may be drilled at the plurality of machining positions 81.

[0017] Furthermore, before performing the above-described machining, the touch probe 15 may be brought into contact with an end 85 of the workpiece 3 (see FIGS. 1 and 6) to acquire the coordinates of the end 85 relative to the robot 11. This allows the control device 11b to determine the overall position of the workpiece 3 and set the workpiece coordinates of the workpiece 3. Furthermore, when the dimensions of the workpiece 3 differ from the machining drawing, the machining position 81 may be determined to match the actual shape of the workpiece 3 by extending, enlarging, or deforming the machining drawing.

[0018] According to this embodiment, even if the workpiece 3 is not accurately positioned relative to the robot 11, holes can be drilled perpendicular to the surface 3a. Furthermore, even if the shape of the workpiece 3 differs from the machining drawing, holes can be drilled perpendicular to the surface 3a in accordance with the shape of the actual workpiece 3. Furthermore, the machining position 81 can be determined at a position that matches the shape of the actual workpiece 3.

[0019] <Embodiment 2> 4, the processing apparatus 100 of this embodiment has a robot 11 and an end effector 113. The end effector 113 has three search cylinders 115. Other structures of the end effector 113 are substantially the same as those of the end effector 13 of the first embodiment. When viewed in the direction of the central axis 13d, the search cylinder 115 is disposed at the vertex of an equilateral triangle with the central axis 13d as the center of gravity. The search cylinder 115 is an air cylinder. The search cylinder 115 has a cylinder body 115a and a search element 115b. The cylinder body 115a extends along the central axis 13d. The search element 115b is a cylinder rod. The search element 115b extends along the central axis 13d and reciprocates within the cylinder body 115a. The search cylinder 115 detects the extension amount of the search element 115b. The search cylinder 115 may extend the search element 115b, and the position where the search element 115b stops may be determined as the search distance.

[0020] A method of using the processing apparatus 100 of this embodiment will be described. The robot 11 positions the end effector 113 so that the central axis 13d passes through the processing position 81 and is approximately perpendicular to the tangent plane 84. Next, the robot 11 extends the probes 115b. When the probes 115b come into contact with the surface 3a, the search distance is measured. The control device 11b calculates the tangent plane 84 from the extension amount of each probe 115b and the posture of the arm 11a.

[0021] Next, the control device 11b positions the end effector 113 so that the central axis 13d is perpendicular to the tangential plane 84 and the machining position 81 passes through the central axis 13d. Next, the main spindle 13c is rotated to perform machining.

[0022] The end effector 113 of this embodiment has a probe 115b in addition to the spindle 13c. Therefore, it is not necessary to replace the drill 17 attached to the spindle 13c with a probe. In addition, since the coordinates of three search positions 83 can be searched at once, the search time can be reduced.

[0023] <Embodiment 3> As shown in FIG. 5, the processing apparatus 200 of this embodiment has a traveling vehicle 25, a robot 11, an exchange device (end effector exchange device) 19, a scanner (3D scanner) 21, a coordinate measuring device 23, a frame 24, and a host control device 29.

[0024] The traveling vehicle 25 has a body 25a, wheels 25b, outriggers 25c, and a plurality of markers 25d. The body 25a may be self-propelled. The outriggers 25c are arranged on the body 25a. During work, the outriggers 25c are extended from the traveling vehicle 25 and fixed to the floor surface 1. The markers 25d are arranged on the ends of the body 25a.

[0025] The workpiece 203 stands on its own on the floor surface 1. The workpiece 203 may be movable. The workpiece 203 has a surface 203a.

[0026] The robot 11 is disposed on a vehicle body 25a. The exchange device 19 is disposed at the tip of the arm 11a. The exchange device 19 can exchange end effectors. The scanner 21 and the end effectors 13 and 113 are attached to the arm 11a via the exchange device 19. The scanner 21 acquires the three-dimensional shape of the surface 203a as a point cloud or a 3D model.

[0027] The coordinate measuring device 23 is supported by a frame 24. The coordinate measuring device 23 is, for example, a laser measuring device. The coordinate measuring device 23 measures the position and orientation of the scanner 21 and the position of the marker 25d. The coordinate measuring device 23 may monitor the position and orientation of the scanner 21 and the position of the marker 25d.

[0028] The host controller 29 generates a 3D model of the surface 203a based on the reference position 11c from the position and orientation of the scanner 21 and the position of the marker 25d. The host controller 29 may generate the 3D model from a point cloud.

[0029] A method of using the processing apparatus 200 of this embodiment will be described. The scanner 21 is moved by the robot 11 in the up-down, left-right, and front-rear directions toward the workpiece 203, and scans the workpiece 203. During this time, the coordinate measuring device 23 monitors the position and orientation of the scanner 21. Based on the position and orientation of the scanner 21 and the scan data, the upper control device 29 generates a 3D model of the surface 203a. The robot 11 has the end effector 13 or the end effector 113 attached to the arm 11a instead of the scanner 21. Based on the 3D model generated by the host controller 29, the host controller 29 determines the processing position 81 and the search position 83. The host controller 29 may calculate the movement trajectory of the arm 11a when searching the surface 203a. As in the first or second embodiment, the host control device 29 calculates the tangent plane 84 at the machining position 81. Then, machining is performed at the machining position 81.

[0030] According to this embodiment, the host control device 29 can acquire the shape of the large workpiece 203 at once. This allows the machining drawing to be matched to the actual shape of the workpiece 203 with high precision.

[0031] If the measurement accuracy of the scanner 21 or the coordinate measuring device 23 is high, the host control device 29 may calculate a tangent plane 84 for the determined machining position 81 .

[0032] <Embodiment 4> 6, the processing apparatus 300 of this embodiment includes a traveling rail 27, an elevated platform cart 325, a robot 11, an exchange device 19, an end effector 13, a marker 11d, a marker 25d, a coordinate measuring device 23, a frame 24, and a host control device 29. Other structures and functions of the processing apparatus 300 of this embodiment are substantially the same as those of the processing apparatus 200 of the third embodiment.

[0033] The traveling rail 27 extends in one direction (X direction) and is arranged on the floor surface 1. The elevated cart 325 has a vehicle body 325a, wheels 325b, outriggers 325c, a lifting platform 325e, and a marker 25d. The elevated cart 325 travels on the traveling rail 27. The elevated cart 325 may be self-propelled. The outriggers 325c are arranged on the vehicle body 325a. The lifting platform 325e is arranged above the vehicle body 325a and moves up and down. The marker 25d is arranged at the end of the lifting platform 325e. The running rail 27 may be omitted.

[0034] The robot 11 is placed on a lifting platform 325e. The robot 11 has an exchange device 19. The exchange device 19 is placed at the tip of the arm 11a, and is equipped with a scanner 21 and an end effector 13. A plurality of markers 11d are placed on the end effector 13. Note that instead of the plurality of markers 11d, a marker 11d and a gyro sensor may be placed. The coordinate measuring device 23 measures and tracks the position of the scanner 21 and the markers 11d and 25d. The host controller 25 controls the aerial vehicle 325 and the robot 11 .

[0035] According to the processing device 300 of this embodiment, the host control device 29 can track the positions of the markers 11d and 25d to determine the installation position and posture of the robot 11. This allows the workpiece 203 to be measured and processed accurately. The elevated platform 325 of the elevated cart 325 can raise and lower the lifting platform 325e to change the height of the robot 11. Even if the height of the workpiece 203 is higher than the movable range of the robot 11, the robot 11 can measure and process the workpiece 203.

[0036] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present invention, and all technical matters included in the technical ideas described in the claims are subject to the present invention. The above-described embodiments are preferred examples, but a person skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in this specification, and these are included in the technical scope described in the appended claims. [Explanation of symbols]

[0037] 3 Work 11 Robots (processing robots) 15 Touch probe (search tool) 17 Drill (machining tool) 115 Search Cylinder (Search Tool) 81 Processing position 83 Machining surface search position 84 contact plane

Claims

1. An end effector attached to a processing robot, Body and a ram installed on the body so as to be able to advance and retreat; a main shaft to which a machining tool can be attached and which is rotatably supported by the ram; Three search cylinders are disposed on the body and arranged to surround the main shaft, each search cylinder comprising: A cylinder body and a probe extending parallel to the main shaft, arranged in the cylinder body so as to be extendable and retractable, and capable of measuring the amount of extension when a tip portion thereof comes into contact with a workpiece; three search cylinders with A machining method for machining the workpiece using an end effector, comprising: the machining robot extends the three search cylinders toward machining surface search positions, which are three points in the vicinity of the machining position of the workpiece, and acquires search coordinates where the search elements come into contact with the machining surface search positions; calculating a tangent plane to the surface of the workpiece at the processing position relative to the processing robot based on the acquired three search coordinates; the machining robot processes the machining position with the machining tool so that the spindle to which the machining tool is attached is perpendicular to the tangential plane; Processing method.

2. The probe is a touch probe. The processing method according to claim 1.

3. The main shaft is disposed on a linear feed shaft, The processing robot stops the arm and causes the linear feed shaft to feed the main shaft, thereby performing processing. The processing method according to claim 1 or 2.

4. The machining tool is a drill, a tap or a reamer. The processing method according to claim 1 or 2.

5. a three-dimensional scanner is attached to the processing robot, and the processing robot moves the arm to generate a three-dimensional model of the surface shape of the workpiece, with a reference position of the processing robot as a reference coordinate; determining the processing position based on the three-dimensional model; The processing method according to claim 3.

6. An end effector attached to a processing robot, Body and a ram installed on the body so as to be able to advance and retreat; a main shaft to which a machining tool can be attached and which is rotatably supported by the ram; Three search cylinders are disposed on the body and arranged to surround the main shaft, each search cylinder comprising: A cylinder body and a probe extending parallel to the main shaft, arranged in the cylinder body so as to be extendable and retractable, and capable of measuring the amount of extension when a tip portion thereof comes into contact with a workpiece; three search cylinders with an end effector having

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